A continuing trend for heavy machinery (machine) is to create interchangeable work implement attachments (attachments) that may be used on a single machine. For example, a machine, such as a skid steer, may have interchangeable attachments, such as a concrete bucket, concrete crusher, digging backhoe, and material bucket, among others. Such attachments are interchangeable through the use of a coupler, where the coupler typically includes two attachment points with each attachment point typically using a locking pin mechanism to couple the attachment to the machine. The efficiency (e.g. speed) and reliability of the coupler for interchanging the attachments is paramount to the function of the machine, as the machine is inoperable for a task without a functioning attachment. Further, the coupler must be capable of maintaining efficiency and reliability in work conditions where gravel, concrete, dust, and debris are present in and around the machine.
Current couplers include manual attachment, dual cylinder hydraulic coupler, and electric actuator attachments. These couplers present practical limitations that may not produce desired efficiency and reliability. For example, the manual coupler provides reliability, but it does not produce desired efficiency as it requires manually interchanging attachments and is a time intensive process.
Conventional dual hydraulic couplers produce increased efficiency over the manual coupler, but often present reliability issues. A typical efficiency of a dual hydraulic coupler is 1.1 seconds to extend the cylinders and 0.45 seconds to retract the cylinders, where watts are equal to 60,401.7 (81 horsepower), at a 11.36 liter per minute flow rate (3 gallon per minute flow rate)), pressure is 32.62 kilograms per square centimeter (kg/sq. cm) (464 pounds per square inch (psi)), and force is equal to 98.71 kilogram meter (714 pounds-force (LBf)). The reliability of the dual hydraulic coupler is dependent on the operation of four hydraulic lines, which are susceptible to malfunction or failure from working conditions or otherwise, which reduces the dual hydraulic coupler's reliability.
Conventional electric actuator couplers produce increased efficiency over the manual coupler, but also present reliability issues. A typical efficiency of an electric actuator coupler is 4.5 seconds to extend the piston and 4.5 seconds to retract the piston, where there is 298.28 watts (0.4 horsepower) based on a voltage of 12 direct current (DC) and a maximum amperage of 26. The reliability of the electric actuator coupler is related to the susceptibility of the electric actuator coupler to malfunction under typical working conditions or otherwise. The electric actuator typically malfunctions during the coupling process, where the electric actuator and the attachment are bound together, such that the manual coupling or uncoupling of the attachment is not possible. An incident of failure when coupling an attachment with the electric actuator coupler typically leads to destruction of the electric actuator coupler as a torch is typically used to cut the electric actuator coupler to free the attachment from the machine.
It is desirable to have a heavy machine coupler with increased efficiency over the manual and electric actuator couplers to reduce the time it take to interchange attachments on the machine. It is further desirable to have a coupler with increased reliability over the dual hydraulic cylinder and electric actuator couplers to reduce coupler malfunction and failure.